The present invention relates to an ignition system for internal combustion engines.
More particularly, it relates to an ignition system for a four-cycle gasoline engine with a static ignition distribution in which a spark plug, an ignition coil and a final stage of a control circuit of the ignition system for individual spark operation is associated with each cylinder. To satisfy the requirements governing harmful exhaust emissions, especially the strict requirements in the U.S., efforts have been made to develop ignition controls ensuring the lowest possible harmful emissions in four-cycle gasoline engines.
An ignition system which can be used for this purpose is known, for example, from the Japanese Patent 56-50263 A.
Methods for monitoring the operation of ignition systems are already known. For example, a method for obtaining the phase signal by means of a Hall sensor is described in DE-OS 36 34 587.
It is possible to detect ignition and explosion with the aid of a pressure sensor or optical sensor in the combustion chamber of every cylinder.
These known ignition controls have the disadvantage that additional sensors must be installed in the ignition system for monitoring operation. This makes the necessary signal detection very costly because of the cost of the sensors themselves on the one hand and because of the manufacturing costs for installing the sensors in the cylinders on the other hand. Moreover, the satisfactory functioning of these additional sensors must be monitored.